[clang] [clang-format] Add --fallback-style to git-clang-format (PR #137609)

[Andrej Pištek via cfe-commits]

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@@ -189,6 +189,13 @@ def main():
         default=config.get("clangformat.style", None),
         help="passed to clang-format",
     ),
+    p.add_argument(
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apdofficial wrote:

Sure, no problem. I rebased the MR with all the changes.

https://github.com/llvm/llvm-project/pull/137609